#!/usr/bin/env python
# -*- coding:utf-8 -*-
'''
import random
print random.random()
print random.randint(1,2)   #包含后面的数
print random.randrange(1,2) #不包含后面的数
'''
import random
checkcode = ''
for i in range(4):  #0-3
    current = random.randrange(0,4) #0-3
    if current != i:
        temp = chr(random.randint(65,90))   #asc码对应的字母
    else:
        temp = random.randint(0,9)
    checkcode += str(temp)
print checkcode
